1. Field of the Invention
The present invention relates to an airbag module cover.
2. Description of the Related Art
Generally, an airbag module has an airbag module cover as an outer shell. In a normal condition (inactive condition), the airbag module cover contains the airbag components such as a folded airbag, an inflator, and so on within its annular wall. In an airbag deployment condition (operating condition), the airbag module cover receives a pressure load from an inflating airbag and is torn along tear lines provided on a back surface of the cover. Then, the torn cover can open as deployment doors and the airbag inflates out from the deployment doors. The airbag module cover mostly has a double-wall structure due to a requisition of an appearance design. An outer wall(s) is provided outside the above-mentioned annular wall in order to provide a better appearance. The airbag module cover, which has overlapped tear lines respectively provided on the double-wall structure, is disclosed (Laid-open Japanese Patent Application No. H5[1993]-262194). The tear lines are formed as grooves having thin-thickness in the above-mentioned airbag module cover.